Efficient quantum state tomography.

  title={Efficient quantum state tomography.},
  author={Marcus Cramer and Martin Bodo Plenio and Steven T. Flammia and Rolando D. Somma and David Gross and Stephen D. Bartlett and Olivier Landon-Cardinal and David Poulin and Yi-Kai Liu},
  journal={Nature communications},
Quantum state tomography--deducing quantum states from measured data--is the gold standard for verification and benchmarking of quantum devices. It has been realized in systems with few components, but for larger systems it becomes unfeasible because the number of measurements and the amount of computation required to process them grows exponentially in the system size. Here, we present two tomography schemes that scale much more favourably than direct tomography with system size. One of them… 

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